21449208 has 64 divisors (see below), whose sum is σ = 59097600. Its totient is φ = 6433280.

The previous prime is 21449203. The next prime is 21449213. The reversal of 21449208 is 80294412.

It is an interprime number because it is at equal distance from previous prime (21449203) and next prime (21449213).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21449201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29473 + ... + 30191.

It is an arithmetic number, because the mean of its divisors is an integer number (923400).

Almost surely, 2^21449208 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21449208, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29548800).

21449208 is an abundant number, since it is smaller than the sum of its proper divisors (37648392).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21449208 is a wasteful number, since it uses less digits than its factorization.

21449208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 852 (or 848 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 21449208 is about 4631.3289669381. The cubic root of 21449208 is about 277.8457471124.

The spelling of 21449208 in words is "twenty-one million, four hundred forty-nine thousand, two hundred eight".